PG MS2250 schematic

[broadz]

hi all, hoping someone can help me!!!

I have am ms2250 that someone has tried to repair before me, and done quite a bad job at it.......
i need a schematic and if possible the bias settings for this amplifier. can anyone help?

thanks

[freshkryp69]

hello and welcome to the phorum!

stick around for awhile and be active on the phorum, make friends and you might get what your needing. If you need repair we have 2 bad ass techs on this phorum if you need a repair thats outta your abilities..

[trickyricky]

PG does not release schematics, but am sure their "techs" will be more than happy to help. Stick around and be active, you'll get plenty of help around here.

[freshkryp69]

hi all, hoping someone can help me!!!

I have am ms2250 that someone has tried to repair before me, and done quite a bad job at it.......
i need a schematic and if possible the bias settings for this amplifier. can anyone help?

thanks

like I said become a active member on here, might take awhile but...youll get the help you need. just stick around and join in conversations get to know people, someone will help you out!!!!

[broadz]

Thanks for the reply however I'm actually working on the amp right now, not in a few months which is what it would take for me to be active and make friends on the forum before being able to source the information I'm in need of. I'm a tech by trade but can't seem to find a schematic to work on my own MS2250. This isn't a customer amp, its my pride and joy, something i've hunted for years to finally source.
As i'm in Australia, it's not even a simple phone call or freight to one of the resident techs. It would be greatly appreciated if someone could forward contact details of someone who may be able to help. Trust me, i'd be willing to share information to a new member much like myself if I could help someone else out.

thanks and regards, Broadz

[joerg]

If the damage is visible with the bare eye u might just post some good pictures here and maybe someone can track the problem down for you.

[broadz]

The visible damage is the easy part. Like I said earlier, someone tried to fix it before me and substituted a lot of components, but not only transistors a lot of incorrect value resistors as well. I have managed to get it going by comparing to the other channel that I think is correct, but there is also a lot of board damage, or lots of lifted tracks. It's been really butchered
I now have 2 issues, a noisy left channel ( sounds like a transistor breaking down) and the clip indicators don't work, even when I drive it into clip with 4 ohm dummy loads on the bench, while watching it on the cro.

This is why I need a schematic, because if a wrong value component is in there - short of an equivalent transistor, it will never work properly

[joerg]

I have a parts board and numerous MS2250´s i could take pictures from specials sections if needed.

[broadz]

I have a parts board and numerous MS2250´s i could take pictures from specials sections if needed.

Thank you for the offer, I may take you up on it, but I have spent too much time on it at the moment that I don't have spare right now, I have a workshop full of paying repairs at the moment and they kinda have to take priority!! The plan for this amp is to go into the wife's car with a nice set of dynaudios but its not a priority.
A schematic would really be better though, but I'll keep looking. Perhaps someone may be prepared to email me one, perhaps even at a price? Just putting it out there!!

[trickyricky]

All (most) old school PG amplifiers where mirror boards meaning they copy and paste for channels. So if you have a working channel then you can copy and paste for the non-working channel (of course one been inverted but that's about the only differences between the two channels).

[broadz]

Almost true. 1 channel is run inverted, but that's to allow ease of bridging and the output stage is the same. I do have 2 channels that work, neither of them quite right and both have been messed with.

I'm not interested in making the amp just work. If I want that, I'll go buy some Sony garbage. I want a beautiful amp, that works 100% to manufacturers spec. If it hadn't been messed with, I can achieve that quite easily with no schematic, but you would struggle to find an area of circuit board bigger than a matchbox that hasn't sustained some kind of damage due to the previous tech.

[broadz]

Hence why I want a schematic!!

[RayBuck]

hi all, hoping someone can help me!!!

I have am ms2250 that someone has tried to repair before me, and done quite a bad job at it.......
i need a schematic and if possible the bias settings for this amplifier. can anyone help?

thanks

Hello I would take pics and post them. The help is on this Phorum just figure out a better way of asking for it.

[Kirghiz]

I'd post pics of what you're dealing with, and I am sure some of the tech guys here will post pics of what the board should look like, and also offer values of the components you need.